> ## Documentation Index
> Fetch the complete documentation index at: https://docs.donnajames.app/llms.txt
> Use this file to discover all available pages before exploring further.

# Introduction

When using [function calling](/rag-from-external-data-provider), you generally need to use publically available APIs - or make your own.

If you would like to suggest a function for us to add, please let us know! You can email us at [info@donnajames.nl](mailto:info@donnajames.nl).

In order to use these tool functions, you must first create your own DONNAJAMES Easy API key. For details, please see [Getting a DONNAJAMES Easy API Key](/api-reference/api-key-setup).

Our current tool functions are:

<CardGroup cols={2}>
  <Card title="weekday" icon="calendar" href="/tools/weekday">
    Get the day of the week for a given date
  </Card>

  <Card title="Coming soon" icon="question">
    Under construction!
  </Card>
</CardGroup>

## Usage

In each tool function's individual page, the description and parameters of the tool are provided. These can be used directly when creating a function in your agent. For example, the settings in the image below are taken directly from the [Weekday](/tools/weekday) page.

<Frame>
  <img src="https://mintlify.s3-us-west-1.amazonaws.com/donnajameseasy/images/tools-intro-1.png" />

  <img src="https://mintlify.s3-us-west-1.amazonaws.com/donnajameseasy/images/tools-intro-2.png" />
</Frame>

For the "Headers" section of the form, you will want to enter the DONNAJAMES Easy API key you created earlier, like so:

```json
{
  "Authorization": "Bearer Your-DONNAJAMES-Easy-API-key-here"
}
```

<Warning>
  You must replace *Your-DONNAJAMES-Easy-API-key-here* with your own API key. The
  tool function will not work otherwise.
</Warning>

And then, just click "Save", and you should be all set!